A randomised trial of selective or routine on-table cholangiography.

To assess the value of pre- and peroperative indicators of common bile duct (CBD) stones, 167 patients undergoing cholecystectomy were randomised to receive either routine (R) or selective (S) on-table cholangiography (OTC). In all, 81/84 patients in the R group and 22/78 in the S group had OTCs (P < 0.0001). In the R group 11/81 were positive (one false-positive) and in the S group 7/22 were positive (P < 0.05). CBD stones were present in 10/81 in the R group and 7/78 in the S group (P = NS). In the R group 8/10 and in the S group 5/7 had CBD stones diagnosed preoperatively by ultrasound scanning (USS), giving USS a positive predictive value (PPV) of 100% and a sensitivity of 71.4% in the S group. A raised preoperative alkaline phosphatase (ALP) was found in 1/10 in the R group and 1/7 in the S group (PPV = 33.3%, sensitivity = 14.3%). In the R group 1/10 and in the S group 1/7 (PPV = 25%, sensitivity = 14.3%) were found to have a dilated CBD during operation suggesting CBD stones. There have been no cases of symptomatic unsuspected retained CBD stones during follow-up to date. Our study has demonstrated that selective use of OTCs can be safely employed in open cholecystectomies. Over 85% (6/7 in the S group and 15/17 overall) of CBD stones can be diagnosed preoperatively by USS and liver function tests, with USS having the greatest PPV and sensitivity.